Episode 120: Old Galaxies, New Problems

About this episode

The episode explores the complexities of early galaxies and the unexpected findings regarding their mass and activity.

We’ve known about the existence of galaxies for about a hundred years, but how well do we actually know the extragalactic universe? In today’s episode, we dive deep on the earliest galaxies in the universe. Sanika covers her first bite on paradoxical galaxies that seem to be the deadest where we expect them to be alivest, and Shashank shows us a source of hidden mass in ancient galaxies that for once isn’t dark matter. Astrobites: The Walking Red: Why are you so quiet and overdense? https://astrobites.org/2026/04/03/walking-red/ Too Massive, Too Early… and Still Not Massive Enough? https://astrobites.org/2026/04/07/too-massive-too-early/ Space Sound: https://www.youtube.com/watch?v=4BPFHTVMmbQ

People in this episode

Guests: Sanika, Shashank

Topics covered

• galaxies
• extragalactic universe
• hidden mass
• dark matter
• paradoxical galaxies

Keywords

• galaxies
• extragalactic
• hidden mass
• dark matter
• paradoxical galaxies
• ancient galaxies

Mentioned in this episode

Organizations: YouTube

Books & works: Astrobites: The Walking Red: Why are you so quiet and overdense?, Too Massive, Too Early… and Still Not Massive Enough?

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